From c1a144d77a6ca3a14ba3c0fec30bc4fd20b3d817 Mon Sep 17 00:00:00 2001 From: Aurelien Jacquiot Date: Tue, 4 Oct 2011 11:00:02 -0400 Subject: [PATCH] C6X: early boot code Original port to early 2.6 kernel using TI COFF toolchain. Brought up to date by Mark Salter This patch provides the early boot code for C6X architecture. There is a 16 entry vector table which is used to direct reset and interrupt events. The vector table entries contain a small amount of code (maximum of 8 opcodes) which simply branches to the actual event handling code. The head.S code simply clears BSS, setups up a few control registers, and calls machine_init followed by start_kernel. The machine_init code in setup.c does the early flat tree parsing (memory, commandline, etc). At setup_arch time, the code does the usual memory setup and minimally scans the devicetree for any needed information. Signed-off-by: Aurelien Jacquiot Signed-off-by: Mark Salter Acked-by: Arnd Bergmann --- arch/c6x/kernel/head.S | 84 ++++++++ arch/c6x/kernel/setup.c | 498 ++++++++++++++++++++++++++++++++++++++++++++++ arch/c6x/kernel/vectors.S | 81 ++++++++ 3 files changed, 663 insertions(+) create mode 100644 arch/c6x/kernel/head.S create mode 100644 arch/c6x/kernel/setup.c create mode 100644 arch/c6x/kernel/vectors.S diff --git a/arch/c6x/kernel/head.S b/arch/c6x/kernel/head.S new file mode 100644 index 0000000..133eab6 --- /dev/null +++ b/arch/c6x/kernel/head.S @@ -0,0 +1,84 @@ +; +; Port on Texas Instruments TMS320C6x architecture +; +; Copyright (C) 2004, 2009, 2010, 2011 Texas Instruments Incorporated +; Author: Aurelien Jacquiot (aurelien.jacquiot@jaluna.com) +; +; This program is free software; you can redistribute it and/or modify +; it under the terms of the GNU General Public License version 2 as +; published by the Free Software Foundation. +; +#include +#include +#include + + __HEAD +ENTRY(_c_int00) + ;; Save magic and pointer + MV .S1 A4,A10 + MV .S2 B4,B10 + MVKL .S2 __bss_start,B5 + MVKH .S2 __bss_start,B5 + MVKL .S2 __bss_stop,B6 + MVKH .S2 __bss_stop,B6 + SUB .L2 B6,B5,B6 ; bss size + + ;; Set the stack pointer + MVKL .S2 current_ksp,B0 + MVKH .S2 current_ksp,B0 + LDW .D2T2 *B0,B15 + + ;; clear bss + SHR .S2 B6,3,B0 ; number of dwords to clear + ZERO .L2 B13 + ZERO .L2 B12 +bss_loop: + BDEC .S2 bss_loop,B0 + NOP 3 + CMPLT .L2 B0,0,B1 + [!B1] STDW .D2T2 B13:B12,*B5++[1] + + NOP 4 + AND .D2 ~7,B15,B15 + + ;; Clear GIE and PGIE + MVC .S2 CSR,B2 + CLR .S2 B2,0,1,B2 + MVC .S2 B2,CSR + MVC .S2 TSR,B2 + CLR .S2 B2,0,1,B2 + MVC .S2 B2,TSR + MVC .S2 ITSR,B2 + CLR .S2 B2,0,1,B2 + MVC .S2 B2,ITSR + MVC .S2 NTSR,B2 + CLR .S2 B2,0,1,B2 + MVC .S2 B2,NTSR + + ;; pass DTB pointer to machine_init (or zero if none) + MVKL .S1 OF_DT_HEADER,A0 + MVKH .S1 OF_DT_HEADER,A0 + CMPEQ .L1 A10,A0,A0 + [A0] MV .S1X B10,A4 + [!A0] MVK .S1 0,A4 + +#ifdef CONFIG_C6X_BIG_KERNEL + MVKL .S1 machine_init,A0 + MVKH .S1 machine_init,A0 + B .S2X A0 + ADDKPC .S2 0f,B3,4 +0: +#else + CALLP .S2 machine_init,B3 +#endif + + ;; Jump to Linux init +#ifdef CONFIG_C6X_BIG_KERNEL + MVKL .S1 start_kernel,A0 + MVKH .S1 start_kernel,A0 + B .S2X A0 +#else + B .S2 start_kernel +#endif + NOP 5 +L1: BNOP .S2 L1,5 diff --git a/arch/c6x/kernel/setup.c b/arch/c6x/kernel/setup.c new file mode 100644 index 0000000..3c2858f --- /dev/null +++ b/arch/c6x/kernel/setup.c @@ -0,0 +1,498 @@ +/* + * Port on Texas Instruments TMS320C6x architecture + * + * Copyright (C) 2004, 2006, 2009, 2010, 2011 Texas Instruments Incorporated + * Author: Aurelien Jacquiot (aurelien.jacquiot@jaluna.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + + +#include +#include +#include +#include +#include +#include + +static const char *c6x_soc_name; + +int c6x_num_cores; +EXPORT_SYMBOL_GPL(c6x_num_cores); + +unsigned int c6x_silicon_rev; +EXPORT_SYMBOL_GPL(c6x_silicon_rev); + +/* + * Device status register. This holds information + * about device configuration needed by some drivers. + */ +unsigned int c6x_devstat; +EXPORT_SYMBOL_GPL(c6x_devstat); + +/* + * Some SoCs have fuse registers holding a unique MAC + * address. This is parsed out of the device tree with + * the resulting MAC being held here. + */ +unsigned char c6x_fuse_mac[6]; + +unsigned long memory_start; +unsigned long memory_end; + +unsigned long ram_start; +unsigned long ram_end; + +/* Uncached memory for DMA consistent use (memdma=) */ +static unsigned long dma_start __initdata; +static unsigned long dma_size __initdata; + +char c6x_command_line[COMMAND_LINE_SIZE]; + +#if defined(CONFIG_CMDLINE_BOOL) +static const char default_command_line[COMMAND_LINE_SIZE] __section(.cmdline) = + CONFIG_CMDLINE; +#endif + +struct cpuinfo_c6x { + const char *cpu_name; + const char *cpu_voltage; + const char *mmu; + const char *fpu; + char *cpu_rev; + unsigned int core_id; + char __cpu_rev[5]; +}; + +static DEFINE_PER_CPU(struct cpuinfo_c6x, cpu_data); + +unsigned int ticks_per_ns_scaled; +EXPORT_SYMBOL(ticks_per_ns_scaled); + +unsigned int c6x_core_freq; + +static void __init get_cpuinfo(void) +{ + unsigned cpu_id, rev_id, csr; + struct clk *coreclk = clk_get_sys(NULL, "core"); + unsigned long core_khz; + u64 tmp; + struct cpuinfo_c6x *p; + struct device_node *node, *np; + + p = &per_cpu(cpu_data, smp_processor_id()); + + if (!IS_ERR(coreclk)) + c6x_core_freq = clk_get_rate(coreclk); + else { + printk(KERN_WARNING + "Cannot find core clock frequency. Using 700MHz\n"); + c6x_core_freq = 700000000; + } + + core_khz = c6x_core_freq / 1000; + + tmp = (uint64_t)core_khz << C6X_NDELAY_SCALE; + do_div(tmp, 1000000); + ticks_per_ns_scaled = tmp; + + csr = get_creg(CSR); + cpu_id = csr >> 24; + rev_id = (csr >> 16) & 0xff; + + p->mmu = "none"; + p->fpu = "none"; + p->cpu_voltage = "unknown"; + + switch (cpu_id) { + case 0: + p->cpu_name = "C67x"; + p->fpu = "yes"; + break; + case 2: + p->cpu_name = "C62x"; + break; + case 8: + p->cpu_name = "C64x"; + break; + case 12: + p->cpu_name = "C64x"; + break; + case 16: + p->cpu_name = "C64x+"; + p->cpu_voltage = "1.2"; + break; + default: + p->cpu_name = "unknown"; + break; + } + + if (cpu_id < 16) { + switch (rev_id) { + case 0x1: + if (cpu_id > 8) { + p->cpu_rev = "DM640/DM641/DM642/DM643"; + p->cpu_voltage = "1.2 - 1.4"; + } else { + p->cpu_rev = "C6201"; + p->cpu_voltage = "2.5"; + } + break; + case 0x2: + p->cpu_rev = "C6201B/C6202/C6211"; + p->cpu_voltage = "1.8"; + break; + case 0x3: + p->cpu_rev = "C6202B/C6203/C6204/C6205"; + p->cpu_voltage = "1.5"; + break; + case 0x201: + p->cpu_rev = "C6701 revision 0 (early CPU)"; + p->cpu_voltage = "1.8"; + break; + case 0x202: + p->cpu_rev = "C6701/C6711/C6712"; + p->cpu_voltage = "1.8"; + break; + case 0x801: + p->cpu_rev = "C64x"; + p->cpu_voltage = "1.5"; + break; + default: + p->cpu_rev = "unknown"; + } + } else { + p->cpu_rev = p->__cpu_rev; + snprintf(p->__cpu_rev, sizeof(p->__cpu_rev), "0x%x", cpu_id); + } + + p->core_id = get_coreid(); + + node = of_find_node_by_name(NULL, "cpus"); + if (node) { + for_each_child_of_node(node, np) + if (!strcmp("cpu", np->name)) + ++c6x_num_cores; + of_node_put(node); + } + + node = of_find_node_by_name(NULL, "soc"); + if (node) { + if (of_property_read_string(node, "model", &c6x_soc_name)) + c6x_soc_name = "unknown"; + of_node_put(node); + } else + c6x_soc_name = "unknown"; + + printk(KERN_INFO "CPU%d: %s rev %s, %s volts, %uMHz\n", + p->core_id, p->cpu_name, p->cpu_rev, + p->cpu_voltage, c6x_core_freq / 1000000); +} + +/* + * Early parsing of the command line + */ +static u32 mem_size __initdata; + +/* "mem=" parsing. */ +static int __init early_mem(char *p) +{ + if (!p) + return -EINVAL; + + mem_size = memparse(p, &p); + /* don't remove all of memory when handling "mem={invalid}" */ + if (mem_size == 0) + return -EINVAL; + + return 0; +} +early_param("mem", early_mem); + +/* "memdma=[@
]" parsing. */ +static int __init early_memdma(char *p) +{ + if (!p) + return -EINVAL; + + dma_size = memparse(p, &p); + if (*p == '@') + dma_start = memparse(p, &p); + + return 0; +} +early_param("memdma", early_memdma); + +int __init c6x_add_memory(phys_addr_t start, unsigned long size) +{ + static int ram_found __initdata; + + /* We only handle one bank (the one with PAGE_OFFSET) for now */ + if (ram_found) + return -EINVAL; + + if (start > PAGE_OFFSET || PAGE_OFFSET >= (start + size)) + return 0; + + ram_start = start; + ram_end = start + size; + + ram_found = 1; + return 0; +} + +/* + * Do early machine setup and device tree parsing. This is called very + * early on the boot process. + */ +notrace void __init machine_init(unsigned long dt_ptr) +{ + struct boot_param_header *dtb = __va(dt_ptr); + struct boot_param_header *fdt = (struct boot_param_header *)_fdt_start; + + /* interrupts must be masked */ + set_creg(IER, 2); + + /* + * Set the Interrupt Service Table (IST) to the beginning of the + * vector table. + */ + set_ist(_vectors_start); + + lockdep_init(); + + /* + * dtb is passed in from bootloader. + * fdt is linked in blob. + */ + if (dtb && dtb != fdt) + fdt = dtb; + + /* Do some early initialization based on the flat device tree */ + early_init_devtree(fdt); + + /* parse_early_param needs a boot_command_line */ + strlcpy(boot_command_line, c6x_command_line, COMMAND_LINE_SIZE); + parse_early_param(); +} + +void __init setup_arch(char **cmdline_p) +{ + int bootmap_size; + struct memblock_region *reg; + + printk(KERN_INFO "Initializing kernel\n"); + + /* Initialize command line */ + *cmdline_p = c6x_command_line; + + memblock_init(); + + memory_end = ram_end; + memory_end &= ~(PAGE_SIZE - 1); + + if (mem_size && (PAGE_OFFSET + PAGE_ALIGN(mem_size)) < memory_end) + memory_end = PAGE_OFFSET + PAGE_ALIGN(mem_size); + + /* add block that this kernel can use */ + memblock_add(PAGE_OFFSET, memory_end - PAGE_OFFSET); + + /* reserve kernel text/data/bss */ + memblock_reserve(PAGE_OFFSET, + PAGE_ALIGN((unsigned long)&_end - PAGE_OFFSET)); + + if (dma_size) { + /* align to cacheability granularity */ + dma_size = CACHE_REGION_END(dma_size); + + if (!dma_start) + dma_start = memory_end - dma_size; + + /* align to cacheability granularity */ + dma_start = CACHE_REGION_START(dma_start); + + /* reserve DMA memory taken from kernel memory */ + if (memblock_is_region_memory(dma_start, dma_size)) + memblock_reserve(dma_start, dma_size); + } + + memory_start = PAGE_ALIGN((unsigned int) &_end); + + printk(KERN_INFO "Memory Start=%08lx, Memory End=%08lx\n", + memory_start, memory_end); + +#ifdef CONFIG_BLK_DEV_INITRD + /* + * Reserve initrd memory if in kernel memory. + */ + if (initrd_start < initrd_end) + if (memblock_is_region_memory(initrd_start, + initrd_end - initrd_start)) + memblock_reserve(initrd_start, + initrd_end - initrd_start); +#endif + + init_mm.start_code = (unsigned long) &_stext; + init_mm.end_code = (unsigned long) &_etext; + init_mm.end_data = memory_start; + init_mm.brk = memory_start; + + /* + * Give all the memory to the bootmap allocator, tell it to put the + * boot mem_map at the start of memory + */ + bootmap_size = init_bootmem_node(NODE_DATA(0), + memory_start >> PAGE_SHIFT, + PAGE_OFFSET >> PAGE_SHIFT, + memory_end >> PAGE_SHIFT); + memblock_reserve(memory_start, bootmap_size); + + memblock_analyze(); + unflatten_device_tree(); + + c6x_cache_init(); + + /* Set the whole external memory as non-cacheable */ + disable_caching(ram_start, ram_end - 1); + + /* Set caching of external RAM used by Linux */ + for_each_memblock(memory, reg) + enable_caching(CACHE_REGION_START(reg->base), + CACHE_REGION_START(reg->base + reg->size - 1)); + +#ifdef CONFIG_BLK_DEV_INITRD + /* + * Enable caching for initrd which falls outside kernel memory. + */ + if (initrd_start < initrd_end) { + if (!memblock_is_region_memory(initrd_start, + initrd_end - initrd_start)) + enable_caching(CACHE_REGION_START(initrd_start), + CACHE_REGION_START(initrd_end - 1)); + } +#endif + + /* + * Disable caching for dma coherent memory taken from kernel memory. + */ + if (dma_size && memblock_is_region_memory(dma_start, dma_size)) + disable_caching(dma_start, + CACHE_REGION_START(dma_start + dma_size - 1)); + + /* Initialize the coherent memory allocator */ + coherent_mem_init(dma_start, dma_size); + + /* + * Free all memory as a starting point. + */ + free_bootmem(PAGE_OFFSET, memory_end - PAGE_OFFSET); + + /* + * Then reserve memory which is already being used. + */ + for_each_memblock(reserved, reg) { + pr_debug("reserved - 0x%08x-0x%08x\n", + (u32) reg->base, (u32) reg->size); + reserve_bootmem(reg->base, reg->size, BOOTMEM_DEFAULT); + } + + max_low_pfn = PFN_DOWN(memory_end); + min_low_pfn = PFN_UP(memory_start); + max_mapnr = max_low_pfn - min_low_pfn; + + /* Get kmalloc into gear */ + paging_init(); + + /* + * Probe for Device State Configuration Registers. + * We have to do this early in case timer needs to be enabled + * through DSCR. + */ + dscr_probe(); + + /* We do this early for timer and core clock frequency */ + c64x_setup_clocks(); + + /* Get CPU info */ + get_cpuinfo(); + +#if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE) + conswitchp = &dummy_con; +#endif +} + +#define cpu_to_ptr(n) ((void *)((long)(n)+1)) +#define ptr_to_cpu(p) ((long)(p) - 1) + +static int show_cpuinfo(struct seq_file *m, void *v) +{ + int n = ptr_to_cpu(v); + struct cpuinfo_c6x *p = &per_cpu(cpu_data, n); + + if (n == 0) { + seq_printf(m, + "soc\t\t: %s\n" + "soc revision\t: 0x%x\n" + "soc cores\t: %d\n", + c6x_soc_name, c6x_silicon_rev, c6x_num_cores); + } + + seq_printf(m, + "\n" + "processor\t: %d\n" + "cpu\t\t: %s\n" + "core revision\t: %s\n" + "core voltage\t: %s\n" + "core id\t\t: %d\n" + "mmu\t\t: %s\n" + "fpu\t\t: %s\n" + "cpu MHz\t\t: %u\n" + "bogomips\t: %lu.%02lu\n\n", + n, + p->cpu_name, p->cpu_rev, p->cpu_voltage, + p->core_id, p->mmu, p->fpu, + (c6x_core_freq + 500000) / 1000000, + (loops_per_jiffy/(500000/HZ)), + (loops_per_jiffy/(5000/HZ))%100); + + return 0; +} + +static void *c_start(struct seq_file *m, loff_t *pos) +{ + return *pos < nr_cpu_ids ? cpu_to_ptr(*pos) : NULL; +} +static void *c_next(struct seq_file *m, void *v, loff_t *pos) +{ + ++*pos; + return NULL; +} +static void c_stop(struct seq_file *m, void *v) +{ +} + +const struct seq_operations cpuinfo_op = { + c_start, + c_stop, + c_next, + show_cpuinfo +}; diff --git a/arch/c6x/kernel/vectors.S b/arch/c6x/kernel/vectors.S new file mode 100644 index 0000000..c95c66f --- /dev/null +++ b/arch/c6x/kernel/vectors.S @@ -0,0 +1,81 @@ +; +; Port on Texas Instruments TMS320C6x architecture +; +; Copyright (C) 2004, 2006, 2009, 2010, 2011 Texas Instruments Incorporated +; Author: Aurelien Jacquiot (aurelien.jacquiot@jaluna.com) +; +; This program is free software; you can redistribute it and/or modify +; it under the terms of the GNU General Public License version 2 as +; published by the Free Software Foundation. +; +; This section handles all the interrupt vector routines. +; At RESET the processor sets up the DRAM timing parameters and +; branches to the label _c_int00 which handles initialization for the C code. +; + +#define ALIGNMENT 5 + + .macro IRQVEC name, handler + .align ALIGNMENT + .hidden \name + .global \name +\name: +#ifdef CONFIG_C6X_BIG_KERNEL + STW .D2T1 A0,*B15--[2] + || MVKL .S1 \handler,A0 + MVKH .S1 \handler,A0 + B .S2X A0 + LDW .D2T1 *++B15[2],A0 + NOP 4 + NOP + NOP + .endm +#else /* CONFIG_C6X_BIG_KERNEL */ + B .S2 \handler + NOP + NOP + NOP + NOP + NOP + NOP + NOP + .endm +#endif /* CONFIG_C6X_BIG_KERNEL */ + + .sect ".vectors","ax" + .align ALIGNMENT + .global RESET + .hidden RESET +RESET: +#ifdef CONFIG_C6X_BIG_KERNEL + MVKL .S1 _c_int00,A0 ; branch to _c_int00 + MVKH .S1 _c_int00,A0 + B .S2X A0 +#else + B .S2 _c_int00 + NOP + NOP +#endif + NOP + NOP + NOP + NOP + NOP + + + IRQVEC NMI,_nmi_handler ; NMI interrupt + IRQVEC AINT,_bad_interrupt ; reserved + IRQVEC MSGINT,_bad_interrupt ; reserved + + IRQVEC INT4,_int4_handler + IRQVEC INT5,_int5_handler + IRQVEC INT6,_int6_handler + IRQVEC INT7,_int7_handler + IRQVEC INT8,_int8_handler + IRQVEC INT9,_int9_handler + IRQVEC INT10,_int10_handler + IRQVEC INT11,_int11_handler + IRQVEC INT12,_int12_handler + IRQVEC INT13,_int13_handler + IRQVEC INT14,_int14_handler + IRQVEC INT15,_int15_handler -- 2.7.4